Endocrine Abstracts

Background: Medullary thyroid carcinoma is a rare type of thyroid cancer that is either sporadic or familial. It occasionally occurs alongside parathyroid hyperplasia and pheochromocytoma as part of MEN2A. Our aim was to study the presence and patterns of above mentioned characteristics of medullary thyroid carcinoma in our population.

Methodology: This is a retrospective study conducted in a tertiary care hospital of Pakistan in which data of medullary thyroid cancer over past 20 years was reviewed. Data from 32 patients was analyzed after fulfillment of the inclusion criteria. Their clinical, pathological, biochemical and treatment outcomes were recorded through retrospective review of their medical record files.

Results: The mean age of patients with medullary thyroid carcinoma (MTC) was 42.88 + 2.67 in our study, with male to female ratio of 2:1. 68.8% of MTC patients were sporadic and 31.2% were familial in our study. 81.3% of patients presented with neck swelling, lymph nodes were palpable in 43.8% of patients and distant metastasis were present in 25% of the patients. The rates of metastasis were highest in bones followed by lungs and liver (12.5%, 9.4%, and 3.1% respectively). Histologically, the mean tumor size was 7.62 + 3.64 with 8 (25%) having distant metastasis. Lymph node metastasis was present in 19 (59.3%) of the patients, out of which 16 had bilateral involvement. Over 50% of carcinomas in our study were unifocal, followed by bifocal (21.9%) and multifocal 3 (9.4%). Mean pre-surgery calcitonin was 11225.7 + 4043.57 which then decreased to a mean of 244.43 + 113.48 post surgery. Mean pre-surgery CEA level was 25.08 + 7.23 which then decreased to 0.0645 + 0.044 post surgery. Hyperparathyroidism was found in two patients while pheochromocytoma was found in one patient only. Two patient were positive for RET gene mutations. Total thyroidectomy was done in 26 (81.2%) of the patients while one patient had subtotal thyroidectomy followed by complete thyroidectomy as initial FNAC was Bethesda category 3. Surgery was not performed in 5 patients due to distant metastasis or palliative intent. Chemotherapy was given to only one patient while XRT was performed in two patients.

Conclusion: Medullary thyroid carcinoma usually presents in fourth decade of life with male predominance and mostly sporadic occurrence. Total thyroidectomy with subsequent serial calcitonin and CEA levels thereafter are the mainstay of treatment and follow-up.